1. Field of the Invention
The present invention relates to the field of liquid crystal display technology, and more particularly, to a source driving module and a liquid crystal display (LCD) panel having the source driving module.
2. Description of the Prior Art
A liquid crystal display (LCD) has such merits of thinness, lightness, power saving, and low radiation as to be applied in notebook computers, mobile phones, electronic dictionaries and other electronic display devices. As per the LCD technology having been developing, so changes the environment in which the electronic display devices are used. They are more often used outdoors. Demand on visual effects is rising, so a LCD device of greater lightness is expected. The LCD panel is a main component of the LCD. The LCD panel includes a color filter substrate, a thin film transistor (TFT) array substrate and a liquid crystal layer therebetween.
The LCD panel is driven by a gate driving module and a source driving module for supplying scan signals and data signals to pixels. Various voltage drops between the data signal and a common voltage induces liquid crystals rotating in different angles to show different brightness, so that the LCD panel shows various grey levels. As shown in FIG. 1, a conventional source driving module includes bi-directional shift registers S/R, latches L, level shifters L/S, digital to analog converters DAC, and buffers B. Digital signals from a timing controller (TCOM) are fed to the latches L via bi-directional shift registers S/R. The level shifters L/S boost voltages of the digital signals, and then the digital to analog converters DAC convert the digital signal into analog signals and transmit to the buffers B. The buffers B output the analog signals to the pixels. As shown in FIG. 1, when there are N pixels arranged in a row, the source driving module supplies N signals to the N pixels. Therefore, the source driving module requires N bi-directional shift registers S/R1˜S/RN, N latches L1˜LN, N level shifters L/S1˜L/NN, N digital to analog converters DAC1˜DACN, and N buffers B1˜BN. Each data input channel has a bi-directional shift register S/R, a latch L, a level shifter L/S, a digital to analog converter DAC, and a buffer B. In other words, there are many pixels in a row, i.e. N is a great integer. The conventional source driving module includes more elements and high cost.